There remains a need to develop effective treatments for subjects suffering from or at risk of a c-Kit and/or c-Fms and/or Flt3 mediated disease or condition. Suitable compounds, including Compound I and Compound II, for the treatment of such diseases and conditions are disclosed in U.S. Pat. No. 7,893,075, U.S. Publication No. 2014-0037617 and U.S. Publication No. 2013-0274259, the disclosures of all of which is incorporated herein by reference in their entirety.
However, Compound I was not heretofore known in any of the specific crystalline forms A-D as described herein. Also, Compound II was not heretofore known in the specific crystalline form as described herein.